| Parameter |
Value |
| Designation |
C/1954 Y1 (Haro-Chavira) |
| Type |
C |
| Perihelion (tp_cal, UTC) |
1956-01-26T17:36:40.613760Z |
| Orbit solution date (soln_date, UTC) |
2021-04-15T23:29:12Z |
| Obs used |
57 |
| NEO |
- |
| M1 |
- |
| K1 |
- |
| PC |
- |
Osculating Elements
| Parameter |
Value |
| Epoch (epoch_cal, TDB) |
1956-08-14.0000000 |
| e |
1.00460292 |
| q (au) |
4.076984 |
| a (au) |
-885.738904 |
| i (deg) |
79.600837 |
| Ω (om, deg) |
72.875012 |
| ω (w, deg) |
57.309578 |
| M (ma, deg) |
0.007488 |
Magnitude
Scatter + Global Linear
$$
M_a = (H_0 + n\cdot 2.5\log_{10} r) + \epsilon - 2.5\log_{10}\Phi(\theta) + 5\log_{10}\Delta
$$
$$
\theta = 180^\circ - \alpha
$$
$$
\Phi(\theta) = \frac{\delta_{90} D(\theta) + 1}{\delta_{90} + 1},\quad D(\theta) = k\cdot \Phi_{HG}(\theta; g_f) + (1-k)\cdot \Phi_{HG}(\theta; g_b)
$$
$$
\Phi_{HG}(\theta; g) = \left(\frac{1+g^2}{1+g^2-2g\cos\theta}\right)^{3/2},\quad \Phi_{HG}(90^\circ)=1
$$
Model Parameters
| Parameter |
Value |
| H0 |
- |
| n |
- |
| gf |
- |
| gb |
- |
| k |
- |
| δ90 |
- |
| Parameter |
Symbol |
Range |
Description |
| Absolute magnitude at 1 AU from Sun and Earth |
H0 |
-5 to 20 |
Intrinsic brightness of the comet |
| Photometric slope parameter |
n |
2 to 6 |
Rate of brightness change with heliocentric distance |
| Forward scattering asymmetry factor |
gf |
0.8 to 1 |
Degree of forward scattering |
| Backward scattering asymmetry factor |
gb |
-1 to -0.5 |
Degree of backward scattering |
| Partitioning coefficient |
k |
0.8 to 1 |
Ratio between forward/backward scattering contributions |
| Dust-to-gas brightness ratio |
δ90 |
1 to 10 |
Relative contribution of dust scattering to gas emission |
Reference: EPSC-DPS2025-160
Ephemeris
| Date/Time (UTC) |
RA (J2000) |
Dec (J2000) |
Nearest HIP |
Dist from HIP (arcmin) |
| 2026-03-26 00:00 |
17:01:16.54 |
-55:13:20.2 |
HIP 83201 |
11.36 |
| 2026-03-26 12:00 |
17:01:15.85 |
-55:13:30.2 |
HIP 83201 |
11.39 |
| 2026-03-27 00:00 |
17:01:15.15 |
-55:13:40.1 |
HIP 83201 |
11.41 |
| 2026-03-27 12:00 |
17:01:14.42 |
-55:13:50.0 |
HIP 83201 |
11.44 |
| 2026-03-28 00:00 |
17:01:13.68 |
-55:13:59.9 |
HIP 83201 |
11.47 |
| 2026-03-28 12:00 |
17:01:12.92 |
-55:14:09.7 |
HIP 83201 |
11.50 |
| 2026-03-29 00:00 |
17:01:12.14 |
-55:14:19.5 |
HIP 83201 |
11.53 |
| 2026-03-29 12:00 |
17:01:11.35 |
-55:14:29.2 |
HIP 83201 |
11.56 |
| 2026-03-30 00:00 |
17:01:10.53 |
-55:14:38.9 |
HIP 83201 |
11.59 |
| 2026-03-30 12:00 |
17:01:09.70 |
-55:14:48.5 |
HIP 83201 |
11.63 |
| 2026-03-31 00:00 |
17:01:08.85 |
-55:14:58.1 |
HIP 83201 |
11.66 |
| 2026-03-31 12:00 |
17:01:07.98 |
-55:15:07.7 |
HIP 83201 |
11.70 |
| 2026-04-01 00:00 |
17:01:07.09 |
-55:15:17.2 |
HIP 83201 |
11.73 |
| 2026-04-01 12:00 |
17:01:06.18 |
-55:15:26.6 |
HIP 83201 |
11.77 |
| 2026-04-02 00:00 |
17:01:05.26 |
-55:15:36.0 |
HIP 83201 |
11.81 |
| 2026-04-02 12:00 |
17:01:04.32 |
-55:15:45.3 |
HIP 83201 |
11.85 |
| 2026-04-03 00:00 |
17:01:03.36 |
-55:15:54.6 |
HIP 83201 |
11.89 |
| 2026-04-03 12:00 |
17:01:02.39 |
-55:16:03.9 |
HIP 83201 |
11.93 |
| 2026-04-04 00:00 |
17:01:01.40 |
-55:16:13.0 |
HIP 83201 |
11.98 |
| 2026-04-04 12:00 |
17:01:00.39 |
-55:16:22.2 |
HIP 83201 |
12.02 |
| 2026-04-05 00:00 |
17:00:59.36 |
-55:16:31.3 |
HIP 83201 |
12.07 |
| 2026-04-05 12:00 |
17:00:58.31 |
-55:16:40.3 |
HIP 83201 |
12.12 |
| 2026-04-06 00:00 |
17:00:57.25 |
-55:16:49.3 |
HIP 83201 |
12.16 |
| 2026-04-06 12:00 |
17:00:56.17 |
-55:16:58.2 |
HIP 83201 |
12.22 |
| 2026-04-07 00:00 |
17:00:55.08 |
-55:17:07.0 |
HIP 83201 |
12.27 |
| 2026-04-07 12:00 |
17:00:53.96 |
-55:17:15.8 |
HIP 83201 |
12.32 |
| 2026-04-08 00:00 |
17:00:52.83 |
-55:17:24.6 |
HIP 83201 |
12.38 |
| 2026-04-08 12:00 |
17:00:51.69 |
-55:17:33.3 |
HIP 83201 |
12.44 |
| 2026-04-09 00:00 |
17:00:50.52 |
-55:17:41.9 |
HIP 83201 |
12.49 |
| 2026-04-09 12:00 |
17:00:49.34 |
-55:17:50.5 |
HIP 83201 |
12.56 |
| 2026-04-10 00:00 |
17:00:48.15 |
-55:17:59.0 |
HIP 83201 |
12.62 |
| 2026-04-10 12:00 |
17:00:46.93 |
-55:18:07.4 |
HIP 83201 |
12.68 |
| 2026-04-11 00:00 |
17:00:45.70 |
-55:18:15.8 |
HIP 83201 |
12.75 |
| 2026-04-11 12:00 |
17:00:44.46 |
-55:18:24.1 |
HIP 83201 |
12.82 |
| 2026-04-12 00:00 |
17:00:43.20 |
-55:18:32.4 |
HIP 83201 |
12.89 |
| 2026-04-12 12:00 |
17:00:41.92 |
-55:18:40.6 |
HIP 83201 |
12.96 |
| 2026-04-13 00:00 |
17:00:40.62 |
-55:18:48.8 |
HIP 83201 |
13.03 |
| 2026-04-13 12:00 |
17:00:39.31 |
-55:18:56.8 |
HIP 83201 |
13.11 |
| 2026-04-14 00:00 |
17:00:37.99 |
-55:19:04.8 |
HIP 83201 |
13.18 |
| 2026-04-14 12:00 |
17:00:36.65 |
-55:19:12.8 |
HIP 83201 |
13.26 |
| 2026-04-15 00:00 |
17:00:35.29 |
-55:19:20.7 |
HIP 83201 |
13.34 |
| 2026-04-15 12:00 |
17:00:33.92 |
-55:19:28.5 |
HIP 83201 |
13.43 |
| 2026-04-16 00:00 |
17:00:32.53 |
-55:19:36.2 |
HIP 83201 |
13.51 |